A174218 An absolute difference sequence based on A087655: a(n)=If[Mod[A087655(n), 3] == 1, a(n - 1) - (-1)^n*n, a(n - 1) + (-1)^n*n]

1, 0, -2, 1, 5, 10, 16, 9, 17, 26, 16, 5, -7, 6, -8, 7, 23, 6, -12, 7, -13, 8, 30, 7, 31, 6, 32, 5, 33, 4, 34, 3, 35, 2, -32, -67, -31, -68, -30, -69, -29, 12, 54, 11, 55, 100, 54, 101, 149, 100, 150, 99, 47, -6, 48, -7, -63, -120, -62, -121, -61, -122, -184, -247, -183

Offset

0,3

Comments

Abs[a(n)-a(n-1)]=n

Links

Table of n, a(n) for n=0..64.

Mathematica

(*A087655[n]*)
Rauzy[n_Integer?Positive] := Rauzy[n] = Rauzy[ Abs[n - Rauzy[n - 1]]] + Rauzy[Abs[n - Rauzy[n - 2]]] + Rauzy[Abs[n - Rauzy[n - 3]]];
Rauzy[0] = Rauzy[1] = Rauzy[2] = Rauzy[3] = 1;
a[0] := 1; a[1] := 0;
a[n_] := a[n] = If[ Mod[Rauzy[n], 3] == 1, a[n - 1] - (-1)^n*n, a[n - 1] + (-1)^n*n];
Table[a[n], {n, 0, 200}]

Crossrefs

Sequence in context: A019098 A333829 A035309 * A226308 A226309 A226311

Adjacent sequences: A174215 A174216 A174217 * A174219 A174220 A174221

Keyword

sign,uned

Author

Roger L. Bagula, Mar 12 2010

Status

approved